Canada's federal environment minister Catherine McKenna made a huge announcement Sunday on Canadian television's Question Period. The central government in Ottawa has come out for nationwide carbon pricing. It will soon levy a minimum national carbon price on any province that lacks adequate plans to reduce its own greenhouse gas emissions.

Many environmentalists argue that Canada’s current goal (cutting GHG emissions to 30% below 2005 levels by 2030), adopted last year by the Conservative Harper government, lacks punch and may be the weakest among leading industrialized nations. Ms. McKenna indicated that for now, Justin Trudeau’s Liberal government will not commit to a more aggressive target. She says, however:

“It’s mandatory that everyone will have to have a price on carbon. If provinces don’t do that, the federal government will provide a backstop."